In accessing services using an electronic device (e.g., a personal computer, a mobile device, etc.), it is typically required for a user of the electronic device to provide a set of username/password pair and/or additional information that can verify an identity of the user. For example, the set of username/password or the additional information may be required when the user intends to execute an operating system (OS) of the electronic device or an application program or to use an online service provided by a website that is only available to registered users.
The set of username/password is typically composed of a string of characters and/or numbers (e.g., several characters followed by several numbers). Input of the set of username/password may be done by the user using an input module such as a physical keyboard or a touch screen displaying a virtual keyboard thereon.
Due to varying security policies of the services, many different sets of username and password may need to be created by the same user to access the different services. Further, requirement for a format of a password or a username may be increasingly complicated nowadays for preventing unauthorized and malicious access. For example, a specific cloud drive service may require a valid password to include at least one upper case letter, at least one lower case letter, and at least one number in order to reduce the risk of the password being cracked.